It's only Anthropic with their current models saying no. Fully autonomous weapons have been created, deployed, and have been operational for a long time already. The only holdout I've ever heard of is for the weapons that target humans.

Honestly, even landmines could easily be considered fully autonomous weapons and they don't care if you're human or not.

There are also good reasons for a lot of countries banning mines. https://en.wikipedia.org/wiki/Ottawa_Treaty

Notably USA is not one of those signatories.